....

I have a feely feel that blond guy is just pretending to be dumb so he could get close with the smart dude whos totally oblivious to his plans hence he calls him "idiot/stupid" cuz he doesnt realize this.

But since its ogawa chise, (i think so?)
Its prolly dark like, that blond guy actually has a grudge on him and want to integrate himself to the smart dude using the tutoring sessions a guise to make him feel comfortable and then blond dude enacts his plans and destroys his body and mind in an act of betrayal for some sort of revenge and ends with the smart guy losing his prestige and future cuz hes been trained to be a submissive toy for this blond dude.

Lol my imagination's running wild hahaha
I love ogawa chise so much TnT